For just capturing some old home movies and burning them to DVD, any cheap software capture card (including a RADEON AIW) should do the trick. VHS tapes have absolutely *horrible* image quality, so it's not like a really nice/expensive card is needed. The software that comes with most of these cards is adequate for just cutting and pasting some video clips and burning tccouhe whole thing to DVD. If you want to get more sophisticated, the sky's the limit (well, that, and the number of zeroes on your bank account balance 😛).
A hardware encoding card is nice if you do a lot of capturing or use it to watch live TV (as it does not eat up 50-100% of your CPU like a software card), but for occasional use it is not necessary IMO.